WARRENVILLE, Ill. – Navistar International Corporation (NYSE: NAV) today announced that it has received certification from the U.S. Environmental Protection Agency (EPA) for its 2011 model year MaxxForce® DT mid-range diesel engine at 0.39 g/bHpHr NOx using Navistar’s in-cylinder NOx reduction technology. This certification represents a 22 percent emissions reduction from the original 0.50g/bHpHr certification and demonstrates progress to achieving the 0.20g/bHpHr standard through base engine and in-cylinder optimization.

“As we’ve said all along, we’re continuing on our path to meeting the latest emissions requirements with the most customer-friendly solutions in the industry,” said Ramin Younessi, group vice president, product development and business strategy, Navistar. “Our product development team has been laser-focused on our 0.20g NOx in-cylinder emissions solution for the past four years.”

Navistar has had continuous success in recent years producing progressively lower emissions diesel engines, phasing in these engines through a process that’s invisible to the customer. In just the past 18 months, Navistar’s MaxxForce engines have ratcheted down NOx emissions by more than 67 percent from 1.2g NOx to 0.9g to 0.5g and today down to 0.39g and beyond.

“Getting to 0.2g NOx through our in-cylinder technologies has always been part of our plan and remains so today,” Younessi added. “Our technology path continues to be a seamless process for our customers where the only thing that changes for them is the EPA label affixed on the engine.”

MaxxForce 15 Certification

Navistar has also received 2010 emissions certification from the EPA and the California Air Resources Board (CARB) for its 2011 MaxxForce 15 big bore diesel engine. The company launched full-scale production of the MaxxForce 15 at its Huntsville, Ala., engine plant in mid-January and the first 2011 model year International® ProStar®+ units with MaxxForce 15 are now making their way into customers’ hands.

MaxxForce 13 at 0.2g NOx Submitted to EPA

In addition, Navistar also recently submitted its MaxxForce 13 at 0.20g NOx for EPA certification, once again reiterating its prime technology path in meeting the 0.20g NOx standard through in-cylinder technologies. The company intends to phase-in its engines at progressively lower NOx emissions levels (0.4g NOx, 0.35g NOx, 0.3g NOx, 0.25g NOx, etc.) in the years ahead in an effort to make emissions compliance as seamless as possible to its customers.

“During the past several years, while other OEMs were producing engines at or above the required emissions standard, Navistar produced engines much cleaner than the standard, in turn, generating credits that today provide us with the flexibility needed to develop the most customer-focused emissions technologies in the industry,” Younessi added. “Our MaxxForce Advanced EGR in-cylinder emissions technology remains the only solution in compliance with EPA standards at the turn of the key, without the need for aftertreatment and without customers having to find and fill liquid urea for their SCR systems.”

All International® brand on-highway commercial vehicles and IC Bus™ brand school and commercial buses for the North American market are powered by MaxxForce engines with MaxxForce Advanced EGR emissions technology. Navistar has pursued its in-cylinder emissions solution path for the past decade to provide the most customer-friendly powertrain in terms of fuel economy, performance and overall ownership costs. With MaxxForce Advanced EGR, customers don’t have the worry or inconvenience of finding or filling liquid urea, as they do with competitors’ SCR systems. MaxxForce-powered trucks and buses require only diesel fuel and operate just as commercial vehicles of the recent past. Most importantly, MaxxForce Advanced EGR provides customers with a no-hassle solution that keeps responsibility for emissions compliance with the manufacturer—not the vehicle owner or driver.

For decades, Navistar has demonstrated its commitment to clean technologies that benefit the environment and its customers. Navistar was the first Original Equipment Manufacturer (OEM) to release the smokeless diesel engine and was the first engine manufacturer to gain EPA certification for meeting 2007 particulate and hydrocarbon emissions standards—six years ahead of schedule. Navistar was also the first OEM to enter line production of diesel-hybrid commercial trucks and school buses in North America. Last year, Navistar launched the eStar™ all-electric truck—the first purpose-built medium-duty all-electric. With zero tailpipe emissions, each eStar truck can reduce greenhouse gas emissions by as much as 10 tons annually.

About Navistar

Navistar International Corporation (NYSE: NAV) is a holding company whose subsidiaries and affiliates produce International® brand commercial and military trucks, MaxxForce® brand diesel engines, IC Bus™ brand school and commercial buses, Monaco® RV brands of recreational vehicles, and Workhorse® brand chassis for motor homes and step vans. The company also provides truck and diesel engine service parts. Another affiliate offers financing services. Additional information is available at www.Navistar.com/newsroom.